Support for concrete reenforcement and joints



Sept. l2, 1933. w. l.. WHITMAN, 2D

SUPPORT FOR CONCRETE REENFORCEMENT AND JOINTS Filed Aug. 20, 1951 .lll

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SUPPORT -FOR CON CRETE REENFRCE- MEN T AND JOINTS Walter L. Whitman, 2d., Philadelphia, Pa.

Application August 20, 1931.

Serial No. 558,297

S Claims. (Cl. 94-51) My invention relates to supports orv installing devices for positioning and supporting dowel bars which are employed as reeniorcement in concrete roadways and the like, yand for supi porting joint material or dividing plates in such roadways. I

In the building of concrete roadways, which are divided into sections, it is common practice to employ dowel pins which extend from the concrete of one section into the concrete of the other section, the bars being imbedded in the concrete during pouring. These bars serve not only as reenforcement for the concrete, but are usually of such thickness that they will support the adjacent portions of such concrete sections in horizontal alinement, that is, they will prevent one section rising or settling with respect to the other section. Furthermore, they serve to prevent breaking olf of portions of the sections along the lineof the joints, and are particularly useful in this respect where a portion of one section may not be properly supported by the subgrade- Heretoiore, dowel bars and other reenforcing bars have been commonly supported upon the sub-grade by what are termed chairs which.

may consist of bent wires or sheet metal stampings that rest upon Ythe sub-grade and carry the reenforcing bars. These chairs become imbedded in the concrete and while they remain there permanently, they perform no useful function except as merely temporary supports for the reenforcing bars. Not only does this procedure involve a waste of material, but the chairs are frequently pushed aside and displaced under the impact of the concrete during pouring.

Furthermore, in the case of a sandy sub-grade, for instance, they may become pushed into the sub-grade somewhat, thus causing the dowel bars to lie out of proper alinement with respect to the plane of the roadway. Portions of displaced bars will be closer to the surface of the roadway than other portions thereof, and if the sub-grade is not perfectly level, some of the bars will be imbedded in the concrete to a greater depth than the other bars. Since traiiic loads are received on the exposed-surface of the concrete, it is important that the bars be positioned parallel to the plane of such surface rather than in dennite relation to the sub-grade.

One object of my invention is to provide an installing device or support which will maintain the dowel bars in proper position, both in horizontal and vertical planes, during pouring of the concrete.

Another object of my invention is to provide means for maintaining the dowel bars in uniform vertically-spaced relation to the surface plane of. the finished roadway, rather than in a predetermined relation to the plane of the sub grade.

A further object of my invention is to provide means for alining and supporting dividing plates or joint strips in a simple and effective manner.

Still another object of my invention is to prow Vide means of generally simplified and improved form for use in installing dowel bars and joints in roadways.`

Some of the forms which my invention may take are shown in the accompanying drawing, wherein Figure l1 is a plan View ofV one form of installing device; Fig. 2 is a side elevational view thereof; Fig. 3 is a view, on an enlarged scale, taken on the line III--III of Fig.v l; Fig. 4 is a fragmentary plan View of a portion of a roadway with the dowel bars and joint installed therein; Fig. 5 is a vertical sectional View thereof; Fig. 6 is a plan View showingra modincation of the structure of Fig. 1; Fig. l is a side elevational View thereof, and Fig. 8 is a cross sectional view, on an enlarged scale.

Referring to Figs. 1, 2 and 8, I show an installing irame which is composed of a pair of angle bars 10 that are secured together by cross platesV 11. or otherwise secured to the plates 11 and serve to maintain a joint strip or plate 13 in longitudinal alinement with the frame 10. Since the frame 10 is rigid, it will, when supported upon side forms l5, serve to maintain the plate 173 in a straight line and prevent it from. being deflected during pouring of the concrete.

In Fig. 3, the joint'strip 13, which may be oi asphalt or other suitable material, is stiened and protected by a metal channel le that is removed after the concrete is poured and the frame 10 taken away. Y

The frame 10 is detachably connected to the side forms 15 by means of hooks V15 that extend through cross pieces 17 andy the angles 10, wing nuts 18 being provided on the threaded ends of the hooks -1.6 for clamping thehooksin place against the anges of the side forms.

The angle plates 12 constitute an important feature of my invention, not only because they serve to aline' theY joint strip, but for the protection which they afford the channel lll. It is the practice to use these channels repeatedly, forV Short angle brackets 12 are riveted iti) protecting and supporting the joint strip durynot be tilted ing pouring of the concrete, the channels being removed from a poured section of roadway and applied to another joint strip, but these channels are frequently bent and dented during pouring, to such an extent that they cannot be placed over another joint strip and hence have to be discarded. The brackets 12 prevent their being bent to such an extent as to become dented or permanently deformed.

During installinfr of the apparatus and previous to pouring of the concrete, dowel bars 19 are inserted through holes in the joint strip 13 and these dowel bars are held in proper vertical and horizontal planes by means of strap-like fingers 20 which are riveted to the angles 1G and are bifurcated at 'their lower ends to straddle the bars 19 adjacent to their ends, thus eliminating chairs which would otherwise'be required to support the ends of the dowel bars, and more rmly holding said bars in position during pouring of the concrete. it will be seen that the bars caneither vertically or 1horizontally. Since the joint strip is always positionedy in deiinite relation to the surface level of the concrete,

the bars 19 will also occupy a definite horizontal Y plane.

Referring new to Figs. 6, '7 and 8, I show a framework that is constructed similarly to the framework of Figs. 1 to 3, but wherein hooksv 16a are of such length that their lower ends may engage under the edge of a completed section of roadway as shown in Fig. i or under the lower edge of a side form instead of under the top flange thereof. Extensions 22 of the hook members 16a facilitates turning thereof into and out of locking position.

A further distinction resides in the provision of angle brackets 12a which are of such length that they extend downwardiy nearly to the sub- This increase in length of the brackets' grade. permits the metal channel 'le of Fig. 3 to be eliminated, since they will serve to support flexible joint material such as heavy paper, felt, etc., against bending under its own weight along'horizontal lines, and also from bending under the weight of the dowel bars 19a. i

Another advantage arising from the use of the angle brackets 12 and 12a is that no te. porary Vpinsneed be driven in the sub-grade against the sides of the joint strip in order'to lmaintain such strip in proper position during pouring.

j It will be understood that after the joint strip and the dowel pins are positioned as shown in the drawing, the concrete is poured and before it is hardened, the installing frame is removed, as is also the strip-supporting channel 14 if such a channel is ernployed, and transferred to another location for a repetition ofthe operations above-described.

I claim as my invention:-- y

1.- A reenforcernent support comprising a frame adapted toA be placed on side forms, in `verticallyspaced relation to and bridging a road bed, and pairs of depending members carried by said frame and having their lower portions formed to abut Y against horizontally-extending `dowel bars, theV members of each pair being spaced laterally of the frame.

2. A supporting device for road joints, comprising a frame adapted to be supported above a road bed on side forms, in position above and parallel to a joint line thereof, depending brackets carried by said frame in position to engage the sides l of a joint strip, and rigidly secured to the said frame at each side of the joint line, for engaging dowel bars which extend through said strip and maintaining them against swinging movement with respect to the strip.

8. A supporting device for road joints, comprising a frame adapted to be supportedabove a road bed on side `forms, in position above and parallel to a joint line thereof, depending brackets carried by said trame in position to engage the sides o1" a joint strip, and vertically-extending members rigidly secured to the said frame at each side of the joint line, for engaging dowel bars which extend throughsaid strip and maintaining thein against swinging movement with respect to the strip, the said members being of uniform. cross-section throughout, whereby removal or the frame is effected without disturbing the position of the strip and the bars.

Ki. An installing device for concrete roadways having a joint strip,` comprising a frame composed of parallel bars having crossplates secured thereto, depei ding brackets secured to said cross plates in position toengage the sides of the joint strip, dowel bars extending through the strip, and depending inernbers secured to said bars for temporarily holdin the dowel bars adjacent to their ends, in a plane parallel with the surface plane of the roadway.

5. An installing device for concrete roadways having a joint strip, comprising a frame composed of parallel ba s having cross plates secured thereto, depending irackets secured to said cross plates in position to engage the sides of the joint strip, dowel bars extending through the strip, and depending members secured to said bars for temporarily holding the dowel bars adjacent to their ends, in a plane parallel with the surface plane of the roadway, andk in predetermined vertically-spaced relation therewith.

6, An installing device for concrete roadways having a joint strip, comprising a frame composed of parallel bars having cross plates secured thereto, depending brackets secured to said cross plates f in position to engage the sides of the joint strip,

`a plurality of dowel bars extending through the temporarily holding the dowel bars in a plane parallel with the surface plane of the roadway.

7. The combination with a member for supporting a dowelbar at its mid portion above a road bed, of a Vpair of Vmembers each formed to engage the bar adjacent to one end thereof, to prevent tilting of the bar, anda device adapted to be supported on side forms in position to bridge the road bed and serving as an alining device and support for said members.

8. The combination with a member forsupporting a dowel bar above a road bed, of a inember for engaging the bar at points removed from said supporting means and shaped to prevent tilting of the bar, and a device adapted to be supported on side forms in position to bridge the road bed and serving as an alining device and support for said members.

WALTER L. WHITMAN, 2D.

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